ELDORET, Kenya — Rival parties in Kenya said Friday they had agreed to take immediate action to end violence after a month of deadly turmoil over a disputed presidential election.

The two sides signed a four-point agenda that said they would complete talks within 15 days on measures to end the political crisis.

"We have agreed (on) an agenda covering both short-term issues and also long-term issues," former U.N. secretary-general Kofi Annan told a news conference after mediating talks with representatives of President Mwai Kibaki and opposition leader Raila Odinga.

More than 800 people have been killed and 300,000 forced from their homes since the disputed Dec. 27 presidential election. Kibaki has made clear that his position as president is nonnegotiable, and the international community has been pressing Kibaki and Odinga to share power.

Much of the bloodshed set off by the political feud has pitted other ethnic groups, including Odinga's Luo tribe, against Kibaki's Kikuyu. Kikuyus, Kenya's largest ethnic group, have long been resented for their dominance of the economy and politics.

On Friday, nine people were killed in western Kenya, including a police officer attacked by a mob of 3,000 armed with bows and arrows, spears, clubs and machetes in the home village of an opposition lawmaker who had been fatally shot by a police officer the day before.

Six people were hacked to death and two killed with poisoned arrows, witnesses said. Nyamira District Commissioner Samuel Njora confirmed the deaths at Ikonge, some 240 miles west of the capital, Nairobi.

The police casualty Friday was the first one authorities have linked to the monthlong postelection turmoil. The mob accused the officer of wounding a civilian Thursday during protests after the killing of lawmaker David Kimutai Too, police commander Peter Aliwa said.

Too's killing added to distrust of police, who are already accused of using excessive force and of being too allied with the government. Police said they had fatally shot four people and wounded five others Thursday evening and Friday morning in western Kenya.

Britain Foreign Office Minister Mark Malloch-Brown suggested deploying Kenya's army, saying Kenyan police "at this stage seem to be seen as no longer neutral and behind some of the killings."

But Kibaki insisted Friday that "the security situation in the country is under control."